Visual rehabilitation using video game stimulation for Stargardt disease

Background: Stargardt disease, a common form of heredomacular degeneration, leads to severe vision loss. Video game play can act as a positive biofeedback to reinforce visual rehabilitation and fixation training. It can potentially lead to visual improvement. This study was done to explore the possibility of visual improvement using video game stimulation for visual rehabilitation in Stargardt disease. Methods: We evaluated eight patients with Stargardt disease who had nonatrophic retina surrounding the area of degeneration at the macula. They underwent extensive baseline testing to determine their Snellen visual acuity, pattern visual evoked potentials, retinal sensitivity, and fixation analysis with microperimetry, electroretinography, fundus photography, optical coherence tomography, and autofluorescence. They were given 40 h of training with video game play and re-evaluated on all the tests. Results: They showed both subjective and objective evidence of improvement in visual functions and vision-related tasks. Visual acuity (from 0.77 ± 0.29 to 0.71 ± 0.32 logMAR, p = 0.027), contrast sensitivity (from 1.28 ± 0.25 to 1.46 ± 0.17, p = 0.002), and fixation stability (log of bivariate contour ellipse area from 6.67 ± 0.52 to 5.85 ± 0.84, p = 0.022) improved significantly. The retinal sensitivity improved by 0.47 ± 3.39 dB ( p = 0.67). Stereopsis and pattern visual evoked potentials showed improvement. A low vision questionnaire documented subjective improvement. Conclusion: Visual stimulation by video game play can result in improvement in visual acuity, fixation pattern, and retinal sensitivity with improvement in vision-related tasks. It can serve as a simple rehabilitatory technique for patients with central vision loss due to Stargardt disease

Localized retinal degeneration secondary to Waldenström's macroglobulinemia

A 52-year-old man, treated for Waldenström's macroglobulinemia (WM), continued to experience decreased vision even after 24 months. He was evaluated using multimodal imaging and electroretinography. The retina did not show any hyperviscosity changes but revealed a yellow lesion at macula with atrophic changes causing a pattern on fluorescein angiography similar to a leopard's skin. Optical coherence tomographic imaging revealed uniformly reflective material deposited in the outer retina with degeneration of outer retinal layers. Full-field electroretinography was normal, but multifocal electroretinography revealed reduced foveal responses. This case highlights the degenerative effects of long-standing immunogammopathy maculopathy in WM

Vitreous opacities after intravitreal triamcinolone injection- a case report

Abstract Background We report occurrence of peculiar tiny white thread like vitreous opacities after intravitreal triamcinolone injection. These persisted without any change for over a year. We ascribe them to aggregation of triamcinolone crystals due to the purification methods. Case presentation Seven patients (8 eyes) with macular edema developed tiny whitish thread like opacities in the vitreous 2–3 months after undergoing an intravitreal injection of triamcinolone acetonide preparation containing benzyl alcohol as preservative. These opacities persisted unchanged for more than a year. The follow up ranged from 91 to 425 days. Vitreous tap was done in one patient which was negative for infection. All patients initially showed improvement but needed re-treatment for recurrence. One patient developed steroid induced rise in intraocular pressure. Microscopic examination of the drug revealed large string like aggregates of triamcinolone crystals. Conclusions We hypothesize the possibility of aggregation of triamcinolone crystals into string like structures probably due to the purification methods used during manufacture which led to these thread like opacities in the vitreous

Comparison between Humphrey Field Analyzer and Micro Perimeter 1 in normal and glaucoma subjects

Purpose: To determine the correlation between fundus perimetry with Micro Perimeter 1 (MP1) and conventional automated static threshold perimetry using the Humphrey Field Analyzer (HFA) in healthy individuals and in subjects with glaucoma. Materials and Methods: In this study, we enrolled 45 eyes with glaucoma and 21 eyes of age-matched, healthy individuals. All subjects underwent complete ophthalmic examination. Differential light sensitivity was measured at 21 corresponding points in a rectangular test grid in both MP1 and HFA. Similar examination settings were used with Goldmann III stimulus, stimulus presentation time of 200 ms, and white background illumination (1.27 cd/m 2 ). Statistical analysis was done with the SPSS 14 using linear regression and independent t-test. Results: The mean light thresholds of 21 matching points in control group with MP1 and HFA were 14.97 ± 2.64 dB and 30.90 ± 2.08 dB, respectively. In subjects with glaucoma, the mean values were MP1: 11.73 ± 4.36 dB and HFA: 27.96 ± 5.41 dB. Mean difference of light thresholds among the two instruments was 15.86 ± 3.25 dB in normal subjects (P < 0.001) and 16.22 ± 2.77 dB in glaucoma subjects (P < 0.001). Pearson correlation analysis of the HFA and MP1 results for each test point location in both cases and control subjects showed significant positive correlation (controls, r = 0.439, P = 0.047; glaucoma subjects, r = 0.812, P < 0.001). There was no difference between nasal and temporal points but a slight vertical asymmetry was observed with MP1. Conclusion: There are significant and reproducible differences in the differential light threshold in MP1 and HFA in both normal and glaucoma subjects. We found a correction factor of 17.271 for comparison of MP1 with HFA. MP1 appeared to be more sensitive in predicting loss in glaucoma

Concurrent retinitis pigmentosa and pigmented paravenous retinochoroidal atrophy phenotypes in the same patient

We report a unique case of a patient with retinitis pigmentosa (RP) phenotype in one eye and pigmented paravenous retinochoroidal atrophy (PPRCA) phenotype in the other eye. We describe in detail the symptoms, clinical findings, and investigations done for a 32-year-old Indian woman. This patient had phenotypical picture resembling typical RP in the right eye, with characteristic symptoms of night blindness and constricted field of vision and a nonrecordable electroretinogram (ERG). The left eye of the same patient revealed typical PPRCA phenotype, with no night blindness, normal field, and normal ERG. RP and PPRCA phenotypes are part of the same spectrum of genetic disorder. However, it is rare to see them coexist in the same patient

Swept-source optical coherence tomography study of choroidal morphology in Stargardt disease

BACKGROUND:Stargardt disease, a juvenile retinal dystrophy, may show secondary changes in the choroid which may have importance while considering future treatments such as stem cell transplant. OBJECTIVE: To evaluate the choroidal and retinal morphology in patients with Stargardt disease and compare with age-matched normals. SETTING AND DESIGN: This was a case–control study at a tertiary level eye care institute. METHODS:Twenty-six patients (52 eyes) clinically diagnosed with Stargardt disease underwent detailed evaluation with swept-source optical coherence tomography. Retinal and choroidal layers were analyzed and compared with 52 eyes of controls. RESULTS: The median age of patients with Stargardt disease was 23 years. The mean best-corrected visual acuity was 0.82 logMAR (20/125 Snellen). Mean diameter of the lesion was 2810.92 ± 1311.15 μ. The lesion size increased with increasing extent of flecks and was significantly correlated with visual acuity (r = 0.622, P < 0.001). The retinal and choroidal thicknesses (CTs) were significantly reduced in Stargardt group. The mean subfoveal CT was 290.59 ± 60.43 μ(range: 184–395) in Stargardt and 331.31 ± 68.90 μ (range: 199–464) in normal group, P = 0.043. CT in Early Treatment Diabetic Retinopathy Study grid pattern showed significant thinning in Stargardt group. The small choroidal vessel (SCV) layer was more affected than the large choroidal vessel (LCV) layer. There was thinning of SCV and thickening of LCV inside the macular lesion. The CT was not correlated to lesion size, extent of flecks, or visual acuity. CONCLUSIONS: Stargardt disease shows generalized thinning of the choroid affecting mainly the SCVs. In the macular lesion, there is atrophy of SCV with compensatory dilation of LCV. The visual acuity did not correlate with CT but showed worsening with increasing lesion size and wider extent of flecks